Energy Efficient Fault Tolerant Sensor Node Failure Detection in WSNs

In WSNs, the large numbers of portable sensor nodes are deployed randomly and can fail due to battery problem, environmental conditions or are unattended. Faulty sensor node detection techniques are mainly affected due to energy consumption of sensor nodes in WSNs. Therefore, the primary goal of this investigation is to design energy efficient fault tolerant sensor node failure detection. A faulty sensor node is detected by measuring the Round Trip Delay (RTD) times of Round Trip Paths (RTPs) in WSNs. Fault tolerance is achieved by assigning unique source node or Cluster Head (CH) for each RTP in WSNs. Energy consumed by individual sensor node is minimized due to optimal involvement of sensor nodes in the detection process. The proposed method is implemented and tested on WSNs with six sensor nodes

Polyaniline assisted USB based sensor for determination of benzene biomarker

Benzene is a known Hemotoxic carcinogen for humans. The carcinogenic properties justify that any exposure to Benzene in ambient air needs to be monitored. Exposure to Benzene is indicated by presence of trans-trans Muconic Acid (ttMA) in urine of human as a biomarker. Currently the levels of biomarker are measured by sophisticated and costly equipment like High Precision Liquid Chromatography (HPLC). This commercial procedure is time consuming due to rigorous sample preparation, involvement of expensive equipment and need of expertise for analysis. To remedy this, USB assisted and Polyaniline (PANI) based point of care electrochemical sensor for detection of biomarker of Benzene is developed. To operate this system, one does not require sample preparation and trained hands.The system is USB based portable potentiostat which performs Linear Sweep Voltammetry (LSV) for detection of ttMA. The design comprises of potentiostat interfaced with microcontroller FRDM-KL 25Z of NXP semiconductors. The system detects nanoampere current with linear sweep voltage resolution of 800 μV. Graphical User Interface (GUI) facilitates to set the parameters like start potential, end potential, step size and scan rate of linear sweep voltage. The real time serial plotter equips the viewing and capture of real-time sensor data from electrochemical cell. The three-electrode electrochemical cell consists of PANI coated Aluminum as working, Graphite Pencil Electrode (GPE) as counter, and Saturated Calomel Electrode (SCE) as reference which is utilized for electrochemical detection of ttMA in urine sample.This system is capable of detecting ttMA in Urine which corresponds to intermediate (1-5 ppm) and high (>5 ppm) level exposure of Benzene in ambient air. Keywords: Linear sweep voltammetry, Trans trans muconic acid, Serial plotter, EM PANI, Graphical user interfac